Justice minister Jeremy Wright said: ”This is an absolutely unacceptable situation, and one which we regret greatly. Clearly this must be distressing for those affected and they can be reassured we are doing everything we can to resolve the situation. The Prison Service is investigating this as a matter of urgency.”

The Prison Reform Trust said it welcomed the immediate apology and investigation.

Its director Juliet Lyon said: ”This is not a matter of dietary preference but of Islamic law. There are clear hospital and prison rules that halal meat must be on the menu.

”This lapse will have offended and distressed high numbers of Muslim prisoners and their families so apologising, suspending the supplier and investigating the incident are the right steps for the Ministry of Justice to take.”